1. Field of the Invention
The present invention relates to a special effect generating system for processing video signals to generate special visual effects to be displayed, and more particularly to a special effect generating system for processing a plurality of video signals supplied from a plurality of video signal sources to generate special visual effects to be displayed.
2. Description of the Prior Art
There is known an electronic editing system which comprises a plurality of video tape recorders, an edit controller, a switcher, and an image converter. After a plurality of video signals reproduced by the respective tape recorders are processed for special effects, the processed video signals are electronically edited, and recorded on another video tape recorder.
As disclosed in Japanese Laid-Open Patent Publication No. 56-62485, for example, the switcher is capable of effecting on the video display screen a transition from an image represented by one video signal to an image represented by another video signal, the new image gradually appearing from one side or corner of the old image. The scene transition is one form of special effect called "wipe."
As disclosed in U.S. Pat. No. 4,965,844, the image converter employs a digital memory, and progressively enlarges or reduces an image represented by a video signal while at the same time progressively shifting the position of the image on a reference screen (i.e., the screen of a television receiver).
The edit controller serves to control the tape transport in the video tape recorders for reproducing video signals and the video tape recorder for recording the edited video signal, and the timing of recording and reproducing the video signals.
In the conventional electronic editing system that incorporates such a special effect generating system, since the switcher and the image converter operate independently of each other, it has been difficult to effect adequate image processing based on a combination of image wipe, image deformation, and image movement.